1. Field of the Invention
This invention relates generally to rollers used in conveyor systems, and more particularly, to conveyor system rollers having modular and removable components that facilitate periodic maintenance of the rollers to replace worn parts, such as bearings, so that the rollers may be reused. The instant invention provides conveyor rollers that can be refurbished instead of completely replaced.
2. Description of Related Art
Conveyor systems are commonly employed in sanitary waste utilities. These conveyor systems use rollers to guide and support the conveyor belt. The rollers known have internally mounted bearings that allow the rollers to easily rotate. Over a period of time, usually 6 to 8 months, the bearings begin to crack and/or wear. This is caused by continuous long term exposure to load and shaft deflection. Under loaded conditions, the bearings are subject to misalignment, loss of bearing surface and pinching between the inter and outer races. This produces additional loading on the bearings which causes increased friction and temperature. The rollers are eventually rendered useless and must be replaced since conventional conveyor system rollers known cannot be easily refurbished with new bearing assemblies, especially in those systems employed by sanitary waste facilities.
A common problem with conventional rollers as used in conveyor systems in the sanitation industry is that the bearings are exposed at the ends of the rollers. As the bearings are not covered they are exposed to the elements such as gases, chemicals and moisture which cause a deterioration and complete breakdown well within a year's time. Consequently, there exists a need for a conveyor system roller that conceals bearings to extend their useful life while providing a way for conveniently replacing the bearings without having to replace the entire roller.
Several rollers for conveyor systems are known in the art. However, none of these provide a conveyor roller for use in sanitation conveyor systems that can be easily refurbished. Some of the rollers known have end caps which are not removable and/or are secured by complicated connectors and hardware which make removal of the end caps time consuming and complicated. For instance, U.S. Pat. No. 4,664,243, issued to Martin, discloses a conveyor or a bearing assembly. The bearing assembly disclosed by Martin has an outer race which is comprised of at least two adjoining and symmetrically mating sections which are held in position by molded projections located on the interior base of these two stabilizing lugs. The interior of the outer race of the spherical bearing is constructed to snugly encompass and rotatably engage the inner race, which comprises a spherical portion having a keyed axial bore and a pair of lateral keyed tubular hubs adjoining said bore on either side of said spherical portion. The bearing assembly disclosed by Martin comprises a single spherical bearing and design which is non-analogous to the problems and structure addressed by the instant invention. U.S. Pat. No. 4,577,747, issued to Martin, comprises a conveyor roller and bearing assembly comprising a tubular modular bearing system. The bearing system is complicated in design and must be completely replaced once it has extended its useful life. The '747 patent issued to Martin is non-analogous to the instant invention inasmuch as it fails to address the same pertinent problems and does not comprise structure for internally mounted bearings. U.S. Pat. No. 4,681,215, also issued to Martin, comprises a conveyor roller and bearing assembly with external support. The conveyor roller and bearing arrangement is rotatable by a pair of fixed stub axles lined between spaced side frame members, including a pair of self-aligning bearing assemblies in each end of the roller. Each bearing assembly in the '215 patent includes an inner bearing race mounted on one stub axle, an outer bearing race rotatably mounted on the inner bearing race and an outer cushioning sleeve secured to the roller and outer bearing race for maintaining axial alignment between the inner and outer bearing races. The '215 patent also represents non-analogous art, fails to disclose the structure contemplated by the present invention. U.S. Pat. No. 1,742,453, issued to Derhoef, discloses roller bearings mounted in bearing recesses wherein the bearings comprise a cup having a tapered surface which is forced into the recess by a pressed fit. The '453 patent is non-analogous to the teachings to the present invention and fails to contemplate the structure of the instant invention.
The foregoing art fails to teach or contemplate bear system rollers having modular and removable components that facilitate periodic maintenance other rollers to replace worn components, such as bearings, so that the rollers may be reused instead of replaced. As such device would provide great cost savings to utilities and other companies employing rollers with internally mounted bearings, the instant invention fills a need in the art.